Effect Of Parameters On Mechanical Properties Of Mortise And Tenon Structures

Most of Chinese traditional architectures and furniture use wood as raw material,and the mortise and tenon structures are the core of wooden structure s which do not have a nail or a riveting and can connect components firmly.C hinese traditional furniture of Ming and Q ing Dynasties applied the mortise and tenon structures into a peak.Although the application of the mortise and tenon structures is more prominent in China,the mortise and tenon structure s of furniture and other wooden structures are often designed by experience and lack of scientific considerations and research on the wood mechanical properties and fit size of mortise and tenon.Besides,research on mortise and tenon structures at home and abroad is still relatively lacking,especially the fit size which impacts on its own strength or other performance.This article classifies the common mortise and tenon structures according to the force type and the purpose of this paper is to analyze the mechanical properties of Chinese traditional mortise and tenon structures by finite element simulation,optimize the parameters of its matching size to get the best fit size and make the ultimate tensile strength,bending strength or other mechanical properties to be the best,which can provide advice on the manufacture of mortise and tenon structures and lay the foundation for the formation of specifications or standards.The main contents are included as follows:(1)The mechanical performance analysis of the common traditional mortise and tenon structures.The mortise and tenon structures in the different parts of furniture joints is not same,stress situation of which is much more complex and often is not under a single kind of stress.According to the main stress situation,the common mortise and tenon structures can be divided into the following categories: the mortise and tenon structures mainly subjected to compressive stress,tensile stress,bending and shearing stress.The mechanical properties of mortise and tenon structures based on the main force characteristics are analyzed by finite element method,and the stress distributions around the mortise and the tenon is obtained and the weakest direction of stress in the joints is pointed out.(2)The parameter optimization analysis of tensile capacity of Dovetail joints.In this paper,Dovetail joints are analyzed by the sequence linear programming optimization method.The effects of different tenon thickness factor w,tenon thickness ratio l and other factors on the tensile capacity of joints are studied.The tenon thickness factor w,the tenon thickness ratio l and the tenon surface angle ? of Dovetail joints are obtained when the tensile capacity is maximum.(3)The parameter optimization analysis of bending moment capacity of T-shaped rectangular joints.In this paper,the T-shaped rectangular joints are analyzed by the sequence linear programming optimization method.The effects of different tenon thickness factor w,the tenon width and thickness ratio l and the interference fit tolerance f on the bending behavior of joints are studied.The tenon thickness factor w,the tenon width and thickness ratio l and the interference fit tolerance f of the T-shaped rectangular joints are obtained when the deflection is minimum,and the weakest direction of stress in the T-shaped rectangular joints of bending test is pointed out.(4)The parameter optimization analysis of ultimate pull-out capacity of T-shaped rectangular joints.Based on the parameter optimization method,the ultimate pull-out performance of T-shaped rectangular joints is analyzed by the finite element method.The effects of different tenon thickness factor w,the tenon width and thickness ratio l and the interference fit tolerance f on the ultimate pull-out capacity of joints are studied.The tenon thickness factor w,the tenon width and thickness ratio l and the interference fit tolerance f of the T-shaped rectangular joints and the relationship between them are obtained when the tension is maximum.